Apparatus for coating printing cylinders



June 422, 1937. c. HENDERSON I APPARATUS FOR COATING PRINTING CYLINDERS 4 Sheets-Sheet 1 Filed Oct. 24, 1935 NNN, Nw/ NMI www, NN, MN QN, um! NN mw QN O llllw IIIIIIIIl I llll Il NN ww Q o M LR -L L.. ,Nw l wm o www Q QN w w mw @N uw NN Q .Q NN v F f,\ Q VA Q@ ar Af@ 726220725077.

June 22, 1937. c. 1 HENDERSON 2,084,642

l APPARTUS FOR COATING PRINTING CYLINDERS Filed oct. 24, 1955- 4 sheets-sheet 2 June 22,'1937. c. 1 HENDERSON APPARATUS FOR COATING PRINTING CYLINDERS Filed Oct. 24; 1935 4 Sheets-Sheet 3 fzwezz? CarZeS fzend'ersofz .June 22, 1937. L, HENDERSON 2,084,642

APPARATUS FOR COATING PRINTING CYLINDERS Filed OCT.. 24, 1955 4 Sheets-Sheet 4A Patented June 22, 19.37v

' UNITED STATES APPARATUS Fon coa'riNG PRINTING CYLIND v ERS Charles L. Henderson, Appleton, Wis., assignor to Paper Patents Company, Neenah, Wis., a

lcorporation of Wisconsin Application October 24, 1935. Serial No. 46.506

14 Claims.

v 'I'his invention relates to the general art of rotogravure printing.' and has reference more particularly to the preparation of the printing cylinders used inI that type of printing. In the practice of preparing such a printing cylinder with the design or pattern in intaglio on the surface thereof, a photographic or other positive of the pattern or design is photographed on to a metal cylinder to the surface of which has been applied a sensitized coating solution that becomes insoluble in water after exposure to light and forms the so-called resist that protects those parts of the cylinder surface that are not to be etched when the etching acid is later applied.

A uniform and even coating of these cylinders with the sensitized resist solution has heretofore been attempted, but, so far as I am aware, has never been successfully accomplished, and the general object of the present invention has been to provide a new and improved apparatus for coating printing cylinders of the type referred to that will be practically successful and will contribute materially to the production of intaglio printing cylinders of superior quality and dura- .,5 bility.

" My invention is based upon the discovery that an even and uniform coating ofthe printing cylinder may be accomplished simply by applying the coating material to the printing cylinder and 30 then rotating the cylinder about its longitudinal axis and also about a vertical axis generally perpendicular to the longitudinal axis during the period when the coating is drying and becoming set. 'I'he coating may be initially applied to the cyl- 35 inder when the cylinder is rotating about its longitudinal axis, as will hereinafter appear, and, if desired, the cylinder may be subjected to flow currents of heated air during the drying operation. v

4 In the accompanying drawings I have illustrated a form of apparatus embodying the principle above outlined, which in practice has demonstrated the soundness of the principle and given satisfactory results; and referring therer t0, i

4') Fig. l is a top plan view of the apparatus, showing the solution-pouring device in working position, and the warm air applying device -in idle position, and the cover of the cylinder housing re- Fig. 2 is a vertical transverse section of the same on line 2-2 of Fig. l, but showing the warm air applying device in working position.

Fig. 3 is an enlarged fragmentary section on 55 the line 3-3 of Fig. 1.

Fig. 4 is an enlarged fragmentary vertical section lengthwise of an air distributing duct on the under side of the cover of the cylinder housing.

Fig. 5 is a bottom plan view of Fig. 4.

Fig. 6 is an enlarged side elevation of the solution container in pouring position and its supporting arm (broken out) on line 6-6 of Figure 1.

Fig. 7 is a front elevation of the spout, valve and drip catcher of the solution container, showing the valve closed and the drip catcher in operative position.

Fig. 8 is a vertical section on the line 6-6 of Fig. 7.

Fig. 9 is a plan section on the line 9-3 of Fig. 6.

In the drawings, I0 designates a hollow cast iron base in which is mounted a xed vertical post Il. Rotatably mounted on post Il by upper and lower anti-friction bearings I2 and I3 is the hub Il of a revoluble circular table I5. On the table I6 are open bearings I6 which receive and journal the ends of the cylinder shaft I6. I9 designates the body of the cylinder, which is 'disposed within a stainless steel rectangular housing 20,- the end walls of which are vertically slotted to admit the shaft ends. The housing has an open top, but after the cylinder is installed the housing is closed by a removable cover 2I for the subsequent coating and drying operations, as more fully explained later. The periphery of the table I5. is also .preferably equipped with an anti-splash guard rim 22, and this, in turn, is encircled by a stationary ring 23 suppgrted by posts 24 from the base I6.

'I'he table I5 is revolved by a variable speed electric motor 25 mounted on one end ofthe base I0, the motor shaft carrying a. pulley 26 that drives a belt 21 encircling the periphery of table I5 and trained over idler guide pulleys 28. The cylinder I9 is revolved on its longitudinal axis by a geared electric motor 29 suspended from the under side of table I5, the gear part of the motor being represented by 36. The shaft of motor 29 carries a pulley 3| which, through a belt 32, drives a pulley 33 removably keyed to the cylinder shaft I8. Collector rings 34 for bringing the current to the motor are fastened to and revolve with the table hub Il, and contact brushes 35 are mounted on the base I0.

One arrangement for applying the coating solution to the cylinder I9 is shown in Figs. 1, 6, '1, 8 and 9, wherein 36 designates an arm that is hinged at 31 to a bracket 38 mounted on the ring 23 and is disposed radially `oi the table I5.

The inner end portion of arm 3 6 is formed as a ring 39 that forms a holder for the solution container vessel 40, which latter has a ange 4| at its upper end that rests on vertical adjusting screws 42 mounted in the ring 139. The vessel is equipped with a cover 43, and centrally of its bottom wall is a tubular neck 44.in the lower end of which is secured a short rubber hose section 45. Clamped on the neck 44 by a block 46 and screws 41 (Fig. 9) is a yoke-'shaped bracket 48, the rear ends of the arms of which are turned downwardly as shown at 49, and in and between the down-turned ends A49 is a pin 50 on whichis pivoted the rear end of a pan 5| that underlies the hose section and forms in effect a valve to open and close the said hose section. 'I'he front end of pan 5| is formed as a spout 52. To the outer sides of the yoke arms are secured forwardly projecting arms 53 in the front ends of which is journaled a rock shaft 54, fast on which are a pair of eccentrics 55. Links 56 mounted on and depending from said eccentrics are pivotally connected at 51 to the sides of the pan 5|. Also keyed on one end of the rock shaft 54 is an arm 58 carrying on its free end a drip catcher 59 which, in the raised cut on position of the valve 5| underlies the spout 52 as shown in Figs. 7 and 8, and, in the lowered qopen position of the Valve 5| is raised out of the way of the spout, as shown in Fig. 6. Fast, on the other end of the shaft 54 is an operating handle 6|). v

When the coating solution is to be applied to 3 the cylinder I9, the long arm 36 carrying the solution container 40 is lowered to horizontal position, as shown in Fig. 6, and, the table and cylinder motors having been started, by the handle 69 the valve 5| is opened as shown in Fig. 6, the drip catcher being simultaneously y elevated out of the way, and the solution ows in a. steady uniform stream onto the top surface of the cylinder I9. Since the cylinder is undergoing rapid revolution both on its own longitudinal axis and sidewise in a horizontal plane, the coating is uniformly distributed overn the entire surface of the cylinder. Excess solution that falls from the cylinder is caught on the bottom of the housing 20 and flows through drain pipes 6| to an underlying gutter 62 mounted on the posts 24, whence it runs to the sewer. At the end of the coating operation, the operating handle 60 is swung in the reverse direction, and this closes the valve 5| and at the same time swings the drip catcher 59 down beneath the spout 52 as shown in Fig. B, so as to prevent the deposit of surplus drops on the surface of the cylinder.

'Ihe solution-applying device is then swung upwardly out of the way, or it may be bodily removed, and the drying device is next brought into operation. 'I'his device is shown in Figs. 1, 2, 3, 4 and 5, wherein 63 designates a tubular arm connected to the discharge side of an air blower filter and heater unit that is mounted on a bracket 64 that may also be secured to the stationary ring 23. In Fig.` 1' the blower is; indicated at 65, the motor at' 66, and the filter casing at 61, the blower 65 being pivotally mounted on the neck of the casing 67. This latter carries a ne mesh screen 68 at its air intake end, one or more electric heaters 69 behind the screen 68, and a body of lter cloth l0 behind the heater 69. It is very important to protect the coating solution from contamination by dust in the operating room, and it is .for this reason that the blower is equipped with means for screening out any dust in the air. The tubular arm 63, like the arm 36, is disposed radially of the table Il, and its inner end is given a funnel formation H which, in the lowered position of the arm 63 shown in Figs. 2, 3 and 4, registers with a central opening 'I2 (Fig. 4) in the cover 2|. To the under side of the cover 2| is attached an air distributing duct 13 that lies above and lengthwise of the cylinder I9. In the central portion of the bottom wall of this duct is a removable ilne screen 14 directly beneath the discharge mouth of the tube 63, which screen is put in place after the solution applying device has been raised; and on either side thereof is a slot 15 that extends substantially to the end of the lduct. The width of each slot may be adjusted to vary the amount of heated air flowing onto the surface of the coated cylinder by means of adjustable strips 'I6 movable toward and from each other by the means clearly indicated in Fig. 5. In the top wall of the cover 2| beyond the ends of the duct |3lare air escape ports 11. To the frame of the screen 14 may be attached a vertical handle 19 (Fig. 4) by which, screen 14 may be placed into position or removed.

During the application of the warm air to dry the cylinder, the cylinder motor 29 and the table motor 25 are kept in operation so that all parts of the surface of the cylinder are uniformly subjected to the action of the heated air. When the cylinder coating has been sufficiently dried, the arm 63 is swung upwardly out of the way, the cover 2| is removed, the cylinder taken out, and an uncoated cylinder inserted in its place.

Briey summarizing the operation, a cylinder is first prepared for coating by smoothing its surface and removing all traces of oxidization or other imperfections andeis then placed immediately, while still wet, in the coating machine. Cover 2| is put in place and both motors started. The roll is then kept wet with a hose up to a few seconds before the coating is applied to insure a uniform condition of the roll surface. The coating is then applied and the coating solution container removed. Screen 'I4 is then dropped in place and the drying air applied until the coating is dry. It is imperative that the roll continue to operate uninterruptedly about both axes from the time the motors are first started until the resist is dry.

From the foregoing it will be seen that the described apparatus enables the cylinder to be first coated and then dried in situ, which is the only way a coating can be successfully applied. To secure the most perfect results it is, of course, necessary to secure a correct coordination of the speed of rotation of the table, the speed of rotation of the cylinder, and the volume of the Warm air supplied during the drying operation, for which latter purpose the tubular arm 63 may be equipped with a shutter or damper '|9. The temperature of the warm air also requires to be nicely regulated; and this may easily be done by regulating the current which supplies the heaters 69.

I have herein shown and described a form of apparatus which I have found by test satisfactori'ly eiectuates the stated purposes and objects of the invention, but manifestly the structural details of this apparatus may be widely' varied within the scope of the invention as delined. in the claims.

I claim:

1. In an apparatus forv coating printing cylinders with a sensitized resist solution, the combination of.` a revoluble table mounted on a vertical axis, means for rotating said table, means for supporting a horizontal cylinder rotatably on said table, means for pouring the coating solution von said cylinder as said table rotates, and means for rotating said cylinder on its longitudinal axis during the pouring operation.

2. In an apparatus for coating printing cylinders with a sensitized resist solution, the combination of a revoluble table mounted on a vertical axis, means for rotating said table, bearings on said table to receive the shaft of a horizontal cylinder, means for pouring the coatlng solution on thel center of said cylinder as said table rotates, and means for rotating said cylinder on its longitudinal axis during vthe pouring operation.

3. In an apparatus for coating printing cylinders with a sensitized resist solution, the combination of a revoluble tableV mounted on a vertical axis, means for rotating said table, bearings on s aid table to receive the shaft of a horizontal cylinder, means for applying the coating solution to said cylinder, means for rotating said cylinder on its longitudinal axis during the applying operation, and means for subjecting the coated surface of the cylinder, while'still revolving about both its vertical and horizontal axes, to a current of heated air.

4. In an apparatus for coating printing cylinders with a sensitized resist solution, the combination of a revoluble table mounted on a vertical axis, means for rotating said table, bearings on said table to receive the shaft of a horizontal cylinder, means for pouring the coating solution on the center of said cylinder as said table rotates, means for rotating said cylinder on its longitudinal axis during the pouring operation, and means for flowing a current of heated air onto the coated cylinder while the latterl is rotating on its longitudinal and vertical axes.

5. In an apparatus for coating printing cylinders with a sensitized resist solution, the combinatlofi of a revoluble table mounted cna vertical axis, means for rotating saidl table, means for supporting a horizontal cylinder rotatably on .saidtabla a motor on said table mechanically connected to the shaft of saidcynnaer for rotating the, latter as said table revolves, and means l for applying the coating solution to said cylinder during the rotating movements of said table and cylinder.

8. In"a cylinder coating apparatus of the character described, the combination of a revoluble table mounted on a vertical axis, means for rotating said table, means for supporting a horizontal cylinderrotatably on said table,.a motor on ma table geared to the shaft of .said cylinder for rotating the latter as said table revolves, means for pouring a coating solution on the center of vsaid cylinder during the rotating movements of said table and cylinder, and means for owing a current of heated ltered air onto the coated cylinder while the latter is rotating on its longitudinal and verticalaxes.

7. In aAcylinder coating apparatus of the character described, the combination of a revoluble table vmounted on ay vertical axis, means for rotating said table, means for supporting a horizontal cylinder rotatably on said table, means for rotating said cylinder on its longitudinal axis, an arm disposed above and radially of said table and horizontally hinged at its outer end, and a solution container mounted on the inner end of said arm, said container having a spout located, directly above the center of said cylinder in ,the lowered position of said arm.

8. In a cylinder coating apparatus of the character described. the combination of a revoluble table mounted on"` a-vertical axis, means for rotating said table, meansfor supporting a hori- .zontal cylinder rotatably on said table, means ing said table, means for supporting a horizontal cylinder rotatably on said table, means for rotating said cylinder on its longitudinal axis, an arm 'disposed above 'and radially of said table and horizontally hinged at its outer end, a solution container mounted on the inner end of said arm, said container having a hinged valve formed with a spout located directly above the center of the cylinder when said arm is lowered and said valve is opened, means vfor opening and closing said valve, and a drip catcherassociated with said valve and spout in a manner to move beneath said spout when said valve is closed and outs from beneath said spout when said valve is opened.

10. In a cylinder coating apparatus of the character described, the combination of a table, means for supporting a cylinder on said table, means for applying a coating solution uniformly to the surfaces of said cylinder, and means for drying said coating solution on the surface of the cylinder comprising an open-top housing.

surrounding the body portion of the cylinder, a removable cover on said housing formed on its under side with an air distributing duct extending lengthwise of the cylinder above the latter and having a longitudinal slot in its bottom wall, and means for supplying heated air to said duct.

11. In a cylinder coating apparatus of the character described, the combination of a table, means for su'p'portlng a cylinder on said table, means for applying a coating solution uniformly to the surface of said cylinder, and means for drying said coating solution on the surface of the cylinder comprising an open-top housing surrounding the body portion of the cylinder, a removable cover on said housing formed on its under side with an air distributing duct extending lengthwise of the cylinder above the latter and having a longitudinal slot in its bottom wall, said cover having air escape ports beyond the ends of said ducts, means for adjusting the width of said slot, and means for supplying heated air to said duct.

12. In a cylinder coating apparatus of the character described, the combination of a table,

'means for supporting a cylinder on said table,

on said housing formed on its under side with an air distributing duct extending lengthwise oi' the cylinder above the latter and having longitudinal slots in its bottom wall, e, tubular arm disposed above and radially of said table and horizontally hinged at its outer end, the inner end of said arm in its lowered position registering with a hole in said cover and communicating with said duct, and means for supplying a current of heated air 10 to the outer end of said arm.

13. In a cylinder coating apparatus of the character described, the combination oi' a table, means for supporting a cylinder-on said table, means for applying a coating solution uniformly 15 to the surface of said cylinder, and means for drying said coating solution on the surface of the cylinder comprising an open-top housing surrounding the body portion of the cylinder, a cover on said housing formed on its under side with an 20 air distributing duct extending lengthwise oi' the cylinder above the latter and having longitudinal slots in its bottom wall, said cover having air escape ports beyond the ends of said ducts. means for adjusting the width of said slots. a tubular arm disposed above and radially of said table and horizontally hinged at its outer end. the inner end of said arm in its lowered position registering with a hole in said cover and communicating with said duct, and a blower and air illter communicating with the outer end oi' said arm.

i4. In an apparatus for coating printing cylinders with a sensitized resist solution, the com bination of a revoluble table mounted on a Vertical axis, means for rotating said table, means for supporting a horizontal cylinder rotatably on said table, means for applying the coating solution to said cylinder, and means for rotating said cylinu der on its longitudinal axis during the applying operation..A 

